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Legionnaires Disease


What is Legionnaires disease?

Legionnaires disease (LD) is a lung infection caused by Legionella bacteria.

How is LD spread?

Legionella bacteria can be found in many water sources. You can get LD by breathing in steam or water droplets that contain Legionella bacteria. LD cannot be passed from one person to another. LD can occur in outbreaks. Outbreaks happen when 2 or more people in the same place develop LD at almost the same time. Legionella bacteria may be found in any of the following:

  • Air-conditioning systems and cooling towers of large buildings
  • Hot water tanks
  • Humidifiers and mechanical ventilators (breathing machines)
  • Lakes, ponds, rivers, streams, and thermal pools
  • Large plumbing systems and bathroom shower heads
  • Water fountains, ice machines, and vegetable misters
  • Whirlpool spas and hot tubs

What increases my risk for LD?

  • Age 65 years or older
  • Smoking or alcohol abuse
  • Heart or lung disease
  • Medical conditions that weaken your immune system, such as HIV

What are the signs and symptoms of LD?

LD symptoms usually appear 2 to 10 days after you are exposed to the bacteria. You may have any of the following:

  • Dry cough and trouble breathing
  • Chills, shaking, or fever
  • Headaches and body pain
  • Nausea, vomiting, and diarrhea
  • Decreased appetite and no energy
  • Dark or bloody urine
  • Trouble thinking clearly and remembering things

How is LD diagnosed?

Your healthcare provider will ask about your symptoms. He may also ask about the places or countries you have visited in the last 2 weeks. He may also ask if you visit spas or use hot tubs often. Tell him if anyone in your home or workplace has had a recent lung infection. You may need any of the following:

  • Blood and urine tests will show if you have an infection.
  • A sputum sample is collected in a cup when you cough. The sample is sent to a lab to be tested for the germ that is causing your infection.
  • Bronchoscopy is a procedure to look inside your airway and learn the cause of your airway or lung condition. A bronchoscope (thin tube with a light) is inserted into your mouth and moved down your throat to your airway. Tissue and fluid may be collected from your airway or lungs and sent to a lab for tests.
  • A chest x-ray may be used to look for signs of pneumonia (lung infection) that can occur with LD.

How is LD treated?

Healthcare providers will give you antibiotics to treat your bacterial infection. The antibiotics may be given through an IV for the first 7 to 10 days. You may also need to continue taking antibiotics by mouth for a period of time.

How can I prevent LD?

You may be able to kill the bacteria that cause LD by regularly cleaning the places they grow. You may need to use a special cleaning fluid to kill the bacteria. Ask your healthcare provider which cleaning fluids you should use.

  • Have your air-conditioning system, hot tubs, or water tanks cleaned regularly.
  • If you have a humidifier, follow the instructions on how to keep it clean.
  • If you use a nebulizer, follow the instructions on how to use and keep your nebulizer clean.

When should I contact my healthcare provider?

  • You have chills, shaking, or fever.
  • You have very dry skin, dry mouth and tongue, or feel very thirsty.
  • You have questions or concerns about your condition or care.

When should I seek immediate care or call 911?

  • You cannot stop vomiting.
  • You cough up blood.
  • You feel dizzy, or have problems thinking clearly and remembering things.
  • You have shortness of breath.
  • You have sudden chest pain.
  • Your symptoms become worse, even after you take your medicine.

Care Agreement

You have the right to help plan your care. Learn about your health condition and how it may be treated. Discuss treatment options with your healthcare providers to decide what care you want to receive. You always have the right to refuse treatment. The above information is an educational aid only. It is not intended as medical advice for individual conditions or treatments. Talk to your doctor, nurse or pharmacist before following any medical regimen to see if it is safe and effective for you.

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Further information

Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.

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